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Oh that sucks, kind of defeats the purpose of mounting two batteries for me.

Do they both discharge at the same time too?

For example, if 2 batteries gave you 4 hours, could you run it for 2 hours, change 1 battery and still have 4 hours to go?

They discharge at the same time as they are just connected in series to get the 14,4V needed (2x7,4V).
You should change them at the same time and only use equally charged (and same capacity) batteries together.

Guess the only advantage is that F970 batteries are cheaper than V-mount batteries and some people might have already lots of them.

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Guess the only advantage is that F970 batteries are cheaper than V-mount batteries and some people might have already lots of them.

Yeah, but even still, I think you'd be better off with one of the smaller sleds that take 1 battery. That way you can just have 3 on rotation and shoot all day long. 1 charging, 1 charged and 1 on the camera. Thanks for the info!

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I have been reading through this thread and I am still looking for a lightweight charging option. I stumbled across this dual battery pack from Tilta for two 18650 batteries. It says it will provide 8v through the dc output, which should be enough to power the camera if attached to a dummy lp-e6 to dc barrel battery? Or am I making any mistakes here?

Not particularly set on the Tilta pack, but in terms of price and mounting options it seems to be the best one for 18650 batteries I have seen so far, or do you have other recommendations?

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this should work, just need to add the right connector and the batteries.

the batbox4k in this thread is very nice, but I did not get a response yet. So I might experiment with the 2.5 euro solution above ... Should give an extra 2h-2h30 on top of the internal battery. 3h useful battery life with a still compact solution would be great !

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I am thinking about going with this core swx battery, since I already use a smallHD focus. I would power the monitor and the camera from this battery, by going to the 12v of the camera from the battery. Do you think this would work? I read earlier in this thread of some concerns of powering a monitor and the camera the same time form the same source, but this seems to be a different type of config

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The Muxtronics man answered : there were still a few little problems, and he has zero time to finish the development.

In the meantime I got this BatPower EX7D 98Wh.

It fits the smallrig powerbank holder on my smallrig cage. Great. The EX7D is about 18cmx2.3cmx8.4 - so is slightly larger than the website & manual state. If the size of the next model is correct, you can get 148 Wh in exactly the same case !

My first tests (after what I think was a full load, but not completely sure about this):

BMCCP4K with an old 4/3 lens with OIS enabled / p4k lcd at 60% / recording to T5 drive :

In theory this would result in 337 min on the BatPower EX7D 98Wh - need to rerun a very long test to confirm this !

Bonus : the powerbank outputs an almost steady 15V. There is also a 20V mode, but that does not seem to work on the p4k (need to test if this is maybe defective ?). When the capacity goes to 0, it switches off. Transition to the internal battery is flawless and recording continues ! This gives at least an extra 44 min to the 270. Or 55 + 337.

In theory, with the 148 Wh version, this results in 7-9h of actual recording time. I think the 98 Wh is enough to get through a full day of (30%?) shooting. You can also charge the powerbank while it is powering the camera ...

The only downside for me is that I expected a slightly smaller enclosure, but it fits the Smallrig holder perfectly. I either mount it on top, or I can hang it under the camera, which is much more stable handheld, but needs some time to put on a tripod.